Bucket conveyor

ABSTRACT

A bucket conveyor for conveying loose grain in different directions, comprising a bucket having: an opening leading to the interior of the bucket; and a dead space constituting part of the interior at the rear, the space not filled with loose grain when grain is loaded from above to or beyond the level of the opening, its volume being larger than the filled volume immediately below the opening. The conveyor does not spill the loose grain even when the angle of the bucket is changed.

TECHNICAL FIELD

[0001] This invention relates to a bucket conveyor. This bucket conveyoris suitable for conveying loose rice, wheat, beans or other farm product(hereinafter, “loose grain”) horizontally, at an incline or vertically.

BACKGROUND ART

[0002] For some time, V-Bucket Conveyor and Pivoted Bucket Conveyor havebeen known as equipment for continuously conveying loose grain fromhorizontal to vertical direction. With the V-Bucket Conveyor, theopening of the bucket is always perpendicular to the direction ofconveyance and the bucket travels through a trough in the horizontaldirection to scoop up the loose grain. Accordingly, friction between thebucket and trough is high which causes high dynamic loss. Also, theloose grain is easily damaged and split open. With the Pivoted BucketConveyor, the bucket is attached to the chain by a pin, therefore theopening of the bucket faces upwards no matter where the bucket islocated. Accordingly, a mechanism is needed to flip the bucket over atthe unloading point and, because the flip roller, cam and bucket aresubjected to considerable shock, structure and materials must bedesigned against shock. Moreover, conveying speed is limited because ofthe flip operation. And, if the loose grain is not loaded in the centerof the bucket, the bucket will tilt and spill the grain. Therefore, adevice is needed to control the relative positions of the loading portand the bucket.

[0003] A bucket conveyor having a rectangular parallelepiped bucket witha 45° angle opening attached to a chain has been proposed for thispurpose (Japanese Utility Model Appln. Laid-Open No.36312/1989). Whenusing this conveyor to transport loose grain, grain gathered under thelower part of the conveyor is scooped up by the bucket on it's returntrip. On the forwarding trip, the opening faces diagonally upward bothin horizontal conveyance and vertical conveyance, and loose grain isfilled up to the diagonal line of the square bucket, thus ½ way full. Onthe returning trip, the opening faces diagonally downward, therefore thebucket dumps the loose grain.

[0004] Other type of bucket conveyor having cylindrical or sphericalbuckets with a similar 45° angle opening, which are attached into acontinuous gapless train has been proposed (Japanese Pat. Appln.Laid-Open No. 072519/1994). When using this conveyor to transport loosegrain, grain is poured from above the bucket and slid along the rear endof the preceding bucket to fall into the opening. Therefore, in additionto the same filling and dumping capacities of the aforementionedproposal, this conveyor has the advantage that loose grain can be loadedcontinuously.

[0005] With the conveyor described in Japanese Utility Model Appln.Laid-Open No. 36312, the loose grain gathered under the conveyor is notcompletely scooped up. Moreover, loose grain is subjected to shock inthe scooping process which damages the grain or splits it open.

[0006] With the conveyor described in Japanese Pat. Appln. Laid-OpenNo.072519, the bucket is only filled ½ full so as not to overflow.Accordingly, it is necessary to control speed of loading the bucket inline with the conveyance speed of the conveyor. Of course, when power islost, the conveyor stops because the control device stops working.However despite this, the loading port remains open and loose grain isloaded continuously until overflowing. In this state, when the conveyoris restarted, loose grain is spilled when the bucket angle changes. Thespilt grain piles up on the bottom of the conveyor which makes it harderto drive the conveyor. Furthermore, it is very troublesome to clean upspilled grain because there is little space between the conveyor caseand bucket.

SUMMARY OF THE INVENTION

[0007] It is an object of this invention to provide a novel conveyor forcontinuously conveying loose grain in different directions, such aschanging from the horizontal to the vertical direction. A further objectis to fill a bucket without damaging the grain before conveyance indifferent directions.

[0008] To achieve the objects of this invention, the conveyor comprisesa bucket which has an opening at the front and a dead space at the rear.The opening leads to the interior of the bucket. The space is not filledwith loose grain when grain is loaded from above to or beyond the levelof the opening; and its volume is larger than the filled volumeimmediately below the opening.

BRIEF DESCRIPTION OF DRAWINGS

[0009]FIG. 1 is a perspective view of the bucket used with an embodimentof the bucket conveyor of this invention;

[0010]FIG. 2 is a sectional view showing the state of the loose grainwhen the bucket of FIG. 1 has a horizontal attitude;

[0011]FIG. 3 is a sectional view showing the bucket in FIG. 2 when stoodin the vertical direction;

[0012]FIG. 4 is a sectional view showing how grain is conveyed using theconveyor;

[0013]FIG. 5 is a front view of a known drive transmission means for theconveyor;

[0014]FIG. 6 is a front view of an improved drive transmission mechanismfor the conveyor;

[0015]FIG. 7 is a plane-sectional view of another embodiment of thebucket conveyor of this invention;

[0016]FIG. 8 is a front sectional view of the conveyor;

[0017]FIG. 9 is a front view partly in of a further another embodimentof the bucket conveyor of this invention;

[0018]FIG. 10 is a X-X sectional view of FIG. 9;

[0019]FIG. 11 is a perspective view of the bucket used with a fourthembodiment;

[0020]FIG. 12 is a sectional view showing how grain is conveyed usingthe conveyor;

[0021]FIG. 13 is a perspective view of the bucket used with a fifthembodiment of the bucket conveyor of this invention;

[0022]FIG. 14 is a cross-sectional view of the bucket introduction;

[0023]FIG. 15 is a cross-sectional view of the bucket main body;

[0024]FIG. 16 is a front view of the bucket conveyer; and

[0025]FIG. 17 is a front view of a sixth embodiment of the bucketconveyer of this invention.

DETAILED DESCRIPTION OF THE INVENTION

[0026] This invented conveyor does not spill the loose grain when theangle of the bucket is changed, even when the bucket has been completelyfilled in appearance, because the grain that was filled to a spaceimmediately below the opening before the bucket's angle is changed fallsinto the dead space. Accordingly, it is possible to change the directionof conveyance from horizontal to vertical while the bucket is full ofloose grain. And, it is possible to position the loose grain loadingport directly over the bucket and fill the bucket under the weight ofthe loose grain because the bucket does not spill the grain even whenfull. As a result, the grain is not damaged by the bucket.

[0027] Loose grain is not spilled even when the bucket is full. For thisreason, the conveyor case is not littered with spilt grain on theinside. And, the conveyor can resume operation immediately after beingstopped without having to control grain loading speed.

[0028] The bucket in this invention idealy has a round rear end surfacecentered on a shaft perpendicular to the plane of the direction ofconveyance, and a front end surface which slides in such way that itcloses the clearance formed with the rear end of the preceding bucket.Though it is not important whether the opening is planar to thedirection of conveyance, part of the rear end surface of the precedingbucket also serves as a part of the front end surface of the followingbucket because the bucket is shaped as previously described.Accordingly, the buckets can be connected in series, which improvesconveyance efficiency.

[0029] The aforementioned front end of the following bucket idealy has asloped surface that contacts the upper half of the rear end surface ofthe preceding bucket. As such, loose grain slides on the front endsurface to be filled completely to the rear except for the dead spacewhen loading, and dumped fast when unloading.

[0030] The bucket in this invention idealy has an apron which extendsperpendicularly to the opening and ahead of the front end surface. Thisapron is connected to the preceding bucket by a common rotating shaft.Because height of the apron exceeds the opening, loose grain does notspill even when the bucket is filled slightly higher than the level ofthe opening. And, because the apron is connected to the preceding bucketby a common rotating shaft, loose grain does not spill even when thebucket is filled slightly higher than the level of the opening when therear end surface of the preceding bucket also serves as the front endsurface of the following bucket.

[0031] This invented conveyor is idealy equipped with a drivetransmission mechanism for endless motion, parallel to a part of theendless path of buckets. By doing so, it is possible to distribute drivepower to multiple buckets without applying excessive load to the drivetransmission mechanism. This differs from the conventional Pivotedbucket Conveyor and V-Bucket Conveyor, in that the chain that links thebuckets is driven by a sprocket and all load is applied to the sprocketpin, therefore the pin is easily worn down.

[0032] The bucket used with this invented conveyor may have holes on thefront end and rear end for a hinge pin. The holes complement the lengthin the shaft direction. As such, the hinge pin hole on the rear end ofthe preceding bucket and the hinge pin hole on the front end of thefollowing bucket form concentric circles and it is possible to securelylink the preceding bucket to the following bucket by passing the hingepin through the holes.

[0033] To achieve the above object, the second invented conveyor whichis related to this invention comprises a bucket which has anintroduction with opening and a main body with dead space, connectedrotationally to the introduction, and is further equipped with guiderails, stationary rail and mobile rail.

[0034] The guide rails are located on both sides of the bucket,supporting and guiding conveyance of the bucket. Because the guide railsare situated on both sides of the bucket, the bucket can smoothly changeangle. The stationary rail is located under the bucket. This rail isstraight in non-unloading position so as to keep the bucket body planarto the direction of conveyance. In unloading position, this railcontinues to support the bucket body and forms a sinusoidal curve sothat the body can rotate on the aforementioned rotating shaft.Accordingly, the bucket travels smoothly over the stationary rail whileunloading its contents as well as when not. For this reason, it is notnecessary to lower conveyance speed when unloading the contents.

[0035] The mobile rail is adjacent to a linear extension of thestationary rail. It substitutes for the stationary rail in the unloadingposition when unloading is unnecessary and thus keeps the bucket bodyplanar to the direction of conveyance. The mobile rail is moved awayfrom the linear extension position when unloading in the unloadingposition. When the bucket is supported by mobil rail, the bucket bodymoves forward without rotating. However, when the mobil rail is removedfrom the bucket, the bucket body is conveyed on the stationary rail androtates at unloading position dumping the contents. Accordingly, it ispossible to freely set whether to unload in the unloading position ornot. And, when these rails are equipped in multiple locations, theunloading position can be selected.

[0036] The bucket may alternatively be supported by guide rail via arotating shaft. In this case it would be desirable to have wheels onboth ends of the rotating shaft. This setup minimizes friction betweenthe rotating shaft and guide rails and allows the bucket to travelsmoothly. And, the aforementioned bucket may be supported by thestationary rail or the mobile rail via roller attached to the bottom ofthe bucket. This setup minimizes friction between the bucket andstationary rail or mobile rail further, and allows the bucket to travelmore smoothly.

[0037] The apron is attached to the introduction surface so as tooverlap the sidewall of the body. The rotating shaft shared with theapron of the following bucket is attached to both sides of the body. Assuch, it is possible to connect all buckets into a gapless train.

[0038] To achieve the above object, the third invented conveyor which isrelated to this invention comprises a bucket which has an introductionwith opening and a main body with dead space, connected rotationally tothe introduction, and guide rails and a swing rail.

[0039] The guide rails are located on both sides of the bucket,supporting and guiding conveyance of the bucket. The swing rail ispositioned pivotally on the horizontal conveyance route, so that whennot unloading, it will be lowered and removed from contact with thebucket body bottom, but when unloading, it is raised to form asinusoidal curve supporting and guiding the bucket bottom at theunloading position so that the bucket body can rotate and dump itscontents. The guide rails will not hinder rotation of the bucket body,since they are situated on both sides of the bucket.

[0040] The bucket is conveyed suspended from guide rails, except when itis unloading. The buckets do not tip out contents as long as there isgapless connection between all buckets. It is also is desirable that thebucket be equipped with rollers at the bottom to come in contact withthe swing rail, so that rotation of the bucket body is achievedsmoothly. The bucket is preferably equipped with protruding wheel shaftson both sides of the introduction, by which it would be suspended fromthe guide rail, and be conveyed smoothly.

[0041] In order to eliminate the gap between the back of the precedingbucket and the introduction of the next bucket, the introductions of thepreceding and following buckets can be coupled with a bar. This barshould be set permanently on the introductions, either by solder or withnut and bolt. It can also be fastened onto the wheel shaft. The bucketbody may also have at the upper portion a flange extending backward torest on the wheel shafts of the following bucket with the aid of theflange. This setup would prevent accidental spillage of contents due tounbalancing of the main body, and at the same time, any loose grainslanding on the bucket upper surface will travel over the flange andslide into the next bucket without spillage.

[0042] When unloading, the swing rail is raised to come in contact withthe bottom surface of the bucket. A sinusoidal curve is formed tosupport and guide the bucket base at the unloading position, so that thebottom will travel slower than the introduction and upper portion of thebucket body. The bucket can thus rotate and dump its contents. Unlikethe second invented conveyor, there is no need for stationary rail.

[0043] To achieve the above object, the fourth invented conveyor whichis related to this invention comprises the bucket of the first inventedconveyor, a hopper and guide rails. The hopper can adjust the feedingport angle by rotating on a support shaft stationed outside the bucketconveyance track. The guide rails for this model are situated on bothsides of the bucket to suspend the buckets for conveyance, in the shapeof a circular arc with a sharp curve under the hopper.

[0044] When grain is loaded from above up to or beyond the level of thebucket opening, a dead space results, constituting part of the interiorat the rear. The space not filled with loose grains has a volume largerthan the filled volume immediately below the opening. The volume of thisdead space is determined by the grain's angle of repose and the bucketangle. Since the angle of repose is characteristic to particular typesof grains and cannot be changed, the angle of the feeding port isadjusted as above, and grain is poured into buckets that are conveyed tocorresponding positions on the guide rails. The bucket will be planar tothe direction of conveyance below the hopper, and tilt upward ordownward in other locations. In this way, the capacity of the dead spacemay be adjusted by the angle of the feeding port of the hopper accordingto need.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] Actual Embodiment 1

[0046] FIGS. 1-6 are used to explain an actual embodiment of the bucketconveyor of this invention.

[0047] As shown in FIG. 1, the bucket (1) is composed of a body (11)which has a U-shape cross-section, and a front end surface (12) which isconnected on a slant to one edge of the body (11). The front end surface(12) is not attached to the body (11) except on the edge shared with thebody (11). The bucket (1) has an opening for loading and unloading,which is bordered with an edge of the front end surface (12) and an edgeon the opposite side of the edge shared between the body (11) and thefront end surface (12). Both side surfaces of the body (11) extendvertically from the opening and forward from the front end surface (12),and serve as aprons (13). Because the aprons (13) are linked on bothsides to the rear end of the preceding bucket by a rotating shaft (15),the front end surface (12) of the following bucket is flexibly contactedwith pressure to the round rear end of the preceding bucket on thetangent of the round rear end. As such, the preceding bucket andfollowing bucket can be connected into a gapless train. Accordingly, thebody (11) has a hole on each side of the front and rear ends forinserting the rotating shaft (15). The bucket (1) rotates on therotating shaft (15) when changing the direction of conveyance fromhorizontal to vertical and vice-versa.

[0048] When the bucket (1) is conveyed horizontally, the body (11)becomes the sideways U-shape seen in FIG. 2. It is presumed that rice isloaded into the bucket from above while the bucket has this attitude.Looking at the bucket (1) itself, the opening is not horizontal.However, because the rear end of the preceding bucket exists over mostof the extended line from the front end surface (12), the rear end ofthe preceding bucket serves as a part of the front end of the followingbucket. Accordingly, the opening is horizontal for all practicalpurposes. Even if rice is loaded up to the top level of opening, thespace (A) determined by the angle of repose α of the rice itself and thedepth X of the body (11) is dead space and is not filled with rice. Ifthe volume of this space (A) is larger than the filled volumeimmediately below the opening (C), because (A+B)≧(B+C), the top surfaceof the rice is below the top level of the opening and the bucket (1)does not spill the rice when the bucket (1) is stood up as shown in FIG.3 (vertical conveyance).

[0049] The following detailed description deals with how rice isconveyed using this bucket conveyor. Referring to FIG. 4, a rice loadingport (14) is provided above the horizontal conveyance forwarding routesufficiently close to the bucket (1). Rice is loaded continuously intothe buckets from the loading port (14). It is not necessary to carefullycontrol loading speed. A small quantity of rice lands on top of the body(11), however it does not fall onto the conveyor floor because thebottom edge of the loading port (14) is lower than the aprons (13). Thebucket (1) rotates on the rotating shaft (15) according to the directionof conveyance. Accordingly, the rice on the top of the body (11) slidesalong the top surface during the vertical conveyance forwarding routeand is guided into the following bucket by the aprons (13). The rice inthe bucket (1) is unloaded into an unloading port (16) when the bucketcomes in the vertical conveyance returning route which causes the riceto slide along the front end (12). Rice falls under its own weight bothwhen loaded into the bucket (1) and when unloaded from the bucket (1),therefore the shock applied to the rice is minimal. For this reason, therice is not damaged.

[0050] Known means can be applied for transmitting drive power to theconveyor. The typical means of transmission has a sprocket (21) at thedirection changing position in the conveyance route of the conveyor, asshown in FIG. 5. In this case, drive is obtained by engaging therotating shaft (15) of the bucket (1) to the sprocket (21). However, inthis method, the load applied to the rotating shaft (15) in thedirection changing position of the bucket (1) is high, thus the sprocket(21) and the rotating shaft (15) are easily worn down.

[0051] Accordingly, this invented conveyor idealy uses a drivetransmission mechanism shown in FIG. 6. In this case, a hook (17) isattached to the bottom of the bucket (1) and wheels (18) are attached toboth ends of the rotating shaft (15). Guide rails (24) are located alongthe conveyance route on both sides of bucket (1). The bucket (1) issupported by the guide rails (24) via the wheels (18) while it is beingconveyed. The drive transmission mechanism consists of a chain (22)which moves endlessly parallel to a part of the endless path of bucket(1), and sprockets (23 and 26) which engage the chain (22). The chain(22) is driven by a motor (25) via one of the sprockets (23) and, whilemoving, it pulls the bucket (1) when the hook (17) catches the chain(22) between front and rear sprockets (23 and 26). Multiple hooks (17),(three shown in figure) are attached to the chain (22), therefore drivepower is distributed and excessive force is not applied to any part. Inparticular, when this drive transmission mechanism is provided for boththe horizontal conveyance route and the vertical conveyance route,excessive stress is not applied to the guide rails or the wheels whenchanging direction. Moreover, because the drive transmission mechanismis provided separately from the endless path of buckets, it can beeasily added to the other preset mechanism.

[0052] Actual Embodiment 2

[0053] This embodiment differs from the bucket used in actual embodiment1 in terms of bucket shape. With actual embodiment 1, because the body(11) has a U-shape of vertical section, the bucket (1) can only turn inthe vertical direction. With this conveyor, conveyance direction can bechanged to the left and right as well.

[0054] Reffering FIGS. 7 and 8, with this conveyor, the rear end of thebucket (3) is basically spherical and is indented from the farthestprotruding point towards the center of the sphere. The bottom of theindent (31) is linked to the front end surface (35) of the followingbucket (3) by a ball-joint (32). The front end surface (35) is curvedinto a round shape when seen in the plane-sectional view, so as tocomplement each other with the rear end surface. The guide rails (33)are located below the bucket (3). The hooks (34) attached to the bottomof the bucket (3) project between the parallel guide rails (33). As withactual embodiment 1, by having the hooks (34) engage the drivetransmission mechanism (2), the bucket (3) is driven in an endlessmotion.

[0055] With this conveyor, not only can conveyance direction be changedfrom horizontal to vertical as shown in FIG. 8, but to the left andright as shown in FIG. 7. Because the buckets (3) are respectivelylinked by ball-joints (32), the buckets (3) do not separate from oneanother during conveyance. Accordingly, the rotating shaft (15) used inactual embodiment 1 is unnecessary.

[0056] Actual Embodiment 3

[0057] With actual embodiment 1, the unloading position is limited to apoint in the returning route where the bucket is turned. Unlike actualembodiment 1, the unloading position of this conveyor can be setrandomly.

[0058] Reffering to FIGS. 9 and 10, with the bucket (4) used on thisconveyor, the body (41) and the front end surface (42) can be separated.Aprons (43) are provided separately from side surface of the body (41).The front end surface (42) is fixed to the aprons (43). As in actualembodiment 1, the body (41) is linked to the aprons (43) of thefollowing bucket (4) by a rotating shaft (44). On both ends of therotating shaft (44), wheels (47) are attached, and the wheels are set onguide rails (46). The guide rails (46) guide the bucket (4) in thedirection of conveyance. The bucket (4) has rollers (45) attached to thebottom, forward of the rotating shaft (44).

[0059] Below the bucket (4) are laid stationary rails (51) on which therollers (45) slide. The width of the stationary rails (51) is half thatof the rollers (45). The stationary rails (51) are straight innon-unloading positions so as keep the body (41) planar to the directionof conveyance. In the unloading position, the stationary rails (51) falland rise to form a sinusoidal curve. Accordingly, the rollers (45)descend smoothly by using the aforementioned rotating shaft (44) as afulcrum when leaving the linear path. The body (41) inclines wherebyunloading the contents. After that, the rollers (45) rise again. Thebody (41) resumes a stable attitude and travels on the linear section ofrailing. In this way, the body (41) travels smoothly on the stationaryrails (51) both while unloading its contents and when not. For thisreason, it is not necessary to lower conveyance speed even whenunloading the contents.

[0060] There are cases when not wanting to unload the contents in theunloading position. For this purpose, mobile rails (52) are provided inthe unloading position. The mobile rails (52) are driven by a motor (53)and can be raised and lowered in the vertical direction via a rack gear(54). The mobile rails (52) substitute for the stationary rails (51) inthe unloading position, acting as an extension (55) of the linearsection of the stationary rails (51). They are positioned next to theextension (55), thus keeping the body (41) planar to the direction ofconveyance. On the other hand, when wanting to unload in the unloadingposition, the mobile rails (52) are lowered away from the position nextto the extension (55). Accordingly, it is possible to freely set whetherto unload in the unloading position or not. And, when the mobile rails(52) are equipped in multiple locations, the unloading position can beselected. The rack gear (54) for raising and lowering the mobile rails(52) can be replaced with a ballscrew or cylinder.

[0061] Actual Embodiment 4

[0062] This embodiment differs from the buckets used in actualembodiments 1 through 3 in terms of bucket shape and coupling means. Inthe aforementioned three types of conveyors, the rear end surface of thebucket is either curved like a U or a hemisphere and, bypress-contacting the front end surface of the following bucket with therear end surface of the preceding bucket, a gapless connection is made.Accordingly, when the direction of conveyance changes, the front endsurface of the following bucket slides on the rear end surface of thepreceding bucket, thus causing friction.

[0063] The bucket conveyor of this actual embodiment couples precedingand following buckets with hinges, therefore sliding surface area isminimized and it is possible to minimize frictional resistance.

[0064] Reffering to FIG. 11, with this conveyor, the bucket (6) isshaped like an unequal-legged trapezoid when viewed as a verticalsection planar to the direction of conveyance. And its internal volumeis the same as with that of actual embodiment 1, which is based on therelation (A+B)≧(A+C). Unlike the aforementioned three actual embodimentshowever, the front end surface (62) is either welded to the body (61) onthe three edges other than the opening edge or is incorporated into asingle body with the body (61) from the very beginning. Both sides ofthe body (61) extend vertically from the opening and serve as aprons(63). This point is the same as on actual embodiment 1.

[0065] The bucket (6) has hinge pin holes (64 and 65 respectively) onthe rear top edge of the body (61) and the top edge of the front endsurface (62). Hinge pin holes (65) are provided on both ends in theshaft direction. The hinge pin hole (64) is concentrically designed soas to be pinched by hinge pin holes (65). The hinge pin holes (64 and65) complement each other so that their total length in the shaftdirection becomes equal to the width of the bucket (6). The hinge pinhole (64) on the preceding bucket and the hinge pin holes (65) on thefollowing bucket form concentric circles and it is possible to securelylink the preceding bucket to the following bucket by passing a hinge pin(66) through the holes. The hinge pin (66) serves as the rotating shaftof the bucket (6). Because the bucket (6) is linked by the hinge on thetop edge of the front and rear ends, the amount of forward projection ofthe aprons (63) is slightly less than that in actual embodiment 1.

[0066] The following detailed description deals with how rice isconveyed using this bucket conveyor. Referring to FIG. 12, as withactual embodiment 1, a rice loading port (14) is provided above thehorizontal conveyance forwarding route sufficiently close to the bucket(6). Rice is loaded continuously into the buckets from the loading port(14). It is not necessary to carefully control loading speed. A smallquantity of rice lands on top of the body (61), however it does not fallonto the conveyor floor because the bottom edge of the loading port (14)is lower than the aprons (63). The bucket (6) rotates on a hinge pin(66) to negotiate the direction of conveyance. Accordingly, the rice onthe top of the body (61) slides along the top surface and into thefollowing bucket during the vertical conveyance forwarding route. Therice in the bucket (6) is unloaded into an unloading port (16) when thebucket comes in the vertical conveyance returning route which causes therice to slide along front end surface (62). With this actual embodimentalso, rice falls under its own weight both when loaded into the bucket(6) and when unloaded from the bucket (6), therefore the shock appliedto the rice is minimal. For this reason, the rice is not damaged.

[0067] Actual Embodiment 5

[0068] As in Actual Embodiment 3, this is an example of a system whereunloading positions can be adjusted at will. However, this model excelsover Embodiment 3 in that it does not require a stationary rail.

[0069] Reffering to FIGS. 13-15, the bucket (7) is composed of a mainbody (71) which has a round rear end, and an introduction (79). Theintroduction (79) has a sloped front end surface (72) and an opening.The body (71) and the introduction (79) are hinged via rotating shaft(74). A wheel shaft (73) is also positioned on the upper edge of frontend surface (72) so that it is perpendicular to the direction ofconveyance and parallel to the level of bucket opening. At the bottom ofthe body (71) are rollers (75). Also, on the upper edge of the body (71)a flange (78) is attached which extends toward the back. The flange (78)is supported by the wheel shaft (73) of the following bucket (7) whenthe body (71) is in its regular position. The guide rail not in thediagram, as in FIGS. 6 and 9, is situated on both sides of the bucket(7) and supports it, guiding it through to the direction of itsconveyance. The ends of the wheel shaft (73) jutting out on both sidesof the bucket (7) are coupled with the wheel shaft on the followingbucket via the bar (70) in order to connect all buckets into a gaplesstrain. The rotating shaft (75) penetrates the bar (70). Therefore, theintroduction (79) is fixed onto the bar (70).

[0070] Under the level of conveyance of the bucket (7), a swing rail(76) is positioned pivotally on the horizontal conveyance route so itcan be moved vertically. When unloading, the swing rail (76) issupported horizontally by a cylinder (77) to form a sinusoidal curvesupporting and guiding the bucket base at the unloading position so thatthe bucket can rotate and dump its contents. Since the swing rail (76)is curved, the rollers (75) move upward on the rail (76) while the wheelshaft (73) travels horizontally. Because of this, the rollers (75)receive opposing force and are delayed behind the wheel shaft (73), withthe result that the body (71) rotates around the rotating shaft (74) andunloads contents. After this, the rollers (75) descend curve over theswing rail (76) so that the body (71) then resumes regular angle.

[0071] When not unloading, the swing rail (76) is lowered bydepressurizing the cylinder (77) and removed from contact with the bodybottom, so that the bucket is conveyed suspended from the guide railsvia the wheel shaft (73). Since the introduction (79) is fixed onto thebar (70), it will not rotate. Neither will the body (71) rotate by theweight of its load since it is also supported by the guide rails via therotating shaft (74) and the wheel shaft (73) of the following bucket(7).

[0072] The flange (78) acts also as a guide to slide loose grain spiltonto the top surface of the body (71) into the following bucket (7).That is, when the bucket (7) is shifting from planar to perpendicularpositions, loose grain lodged onto the top surface of the body (71)slides over the flange (78) down to the introduction (79) of thefollowing bucket (7).

[0073] For the swing rail (76) drive force can be supplied either bycylinder or motor in combination with pinion racks, and other knownmethods.

[0074] Actual Embodiment 6

[0075] In the previous embodiments, when grain is loaded from above upto or beyond the level of the bucket opening, a dead space results,constituting part of the interior at the rear. The space not filled withloose grains must have a volume being larger than the filled volumeimmediately below the opening. The volume of this dead space isdetermined by the grain's angle of repose and the bucket angle. However,angle of repose is characteristic to each grain type and cannot bechanged. Depending on the grain type and characteristic, the capacity ofthis dead space may not fulfill the aforesaid requisite of (A+B)≧(B+C).The amount of grain fed into each bucket (B+C) is adjusted here bycontrolling the angles of feeding port and bucket.

[0076] The bucket 6 is identical to that in Actual embodiment 4.However, this example includes hopper (82) and guide rail (83). Thehopper (82) is situated to be swung in pendulum fashion on the supportshaft (84) stationed above the bucket conveyance track. On one side ofthe hopper (82) one end of the bolt (85) is pivotally attached. Theother end of the bolt (85) penetrates hole (87) on a stationarystructure (86) such as a wall or frame. The hopper (82) can be fixed ata stationary angle with nuts (88) and (89). The guide rails (83) are onboth sides of the bucket (6) and are supporting the wheel shaft(66). Theguide rails (83) are straight apart from corners, but is elliptical inthe proximity of hopper (82). The radius is smallest directly below thesupport shaft (84).

[0077] The bucket (6) resumes planar position directly below the supportshaft (84), When less grain content (B+C) and larger dead space A isdesired, the hopper (82) is tilted toward lower right side as shown insolid line, and grain fed onto bucket in downward tilted position. Whenmore grain content (B+C) and less dead space A is desired, the hopper(82) is tilted to lower left, so as to feed grain onto bucket in upwardtilted position. In this way, the size of dead space may be adjusted bychanging the grain feeder angle.

[0078] Note that even though buckets shown in above example are depictedas having parallel upper and lower sides, this need not always be thecase.

What is claimed is:
 1. A bucket conveyor for conveying loose grain, inwhich the bucket angle must inevitably change according to the directionof conveyance, said conveyor comprising a bucket having: an openingleading to the interior of the bucket at the front; and a dead spaceconstituting part of the interior at the rear, the space not filled withloose grain when grain is loaded from above to or beyond the level ofthe opening, its volume being larger than the filled volume immediatelybelow the opening.
 2. The conveyor of claim 1 , further comprising asecond bucket preceding the bucket, wherein the first bucket has a roundrear end surface centered on a shaft perpendicular to the plane of thedirection of conveyance, and a front end surface which slides so as toclose the clearance formed with the rear end of the second bucket. 3.The conveyor of claim 2 , wherein the front end surface is sloped so asto contact the upper half of the rear end surface of the second bucket.4. The conveyor of claim 2 , wherein the first bucket has an apron whichextends perpendicularly to the opening and ahead of the front endsurface, the apron connected to the second bucket by a common rotatingshaft.
 5. The conveyor of claim 1 , further comprising a drivetransmission mechanism parallel to a part of the endless path of thebucket, the mechanism making endless motion.
 6. The conveyor of claim 1, further comprising a second bucket preceding the first bucket, whereinthe first bucket has holes on the front end and rear end for a hinge pinto be linked to the second bucket by passing the hinge pin through theholes
 7. The conveyor of claim 1 , wherein the bucket is composed of anintroduction with the opening, and a main body with the dead space, saidbody rotatably connected to the introduction.
 8. A bucket conveyor forconveying loose grain, in which the bucket angle must inevitably changeaccording to the direction of conveyance, said conveyor comprising: abucket composed of an introduction and a main body, the introductionhaving an opening introducing grain into the bucket, the body rotatablyconnected having a dead space not filled with grain when grain is loadedfrom above to or beyond the level of the opening, its volume beinglarger than the filled volume immediately below the opening; guide railslocated on both sides of the bucket, supporting and guiding it in thedirection of conveyance, a stationary rail located under the bucket,said rail being straight in non-unloading position so as to keep thebody planar to the direction of conveyance and in the unloading positionforming a sinusoidal curve so as to enable the body to rotate whilesupporting the body; and a mobile rail positioned in the unloadingposition to be adjacent to a linear extension of the stationary rail andbeing able to move away from the linear extension position.
 9. Theconveyor of claim 8 , wherein the bucket is supported by the guide railsvia a rotating shaft.
 10. The conveyor of claim 8 , wherein the body isequipped with a roller at the bottom.
 11. A bucket conveyor forconveying loose grain, in which the bucket angle must inevitably changeaccording to the direction of conveyance, said conveyor comprising: abucket composed of an introduction and a main body, the introductionhaving an opening introducing grain into the bucket, the body rotatablyconnected having a dead space not filled with grain when grain is loadedfrom above to or beyond the level of the opening, its volume beinglarger than the filled volume immediately below the opening; guide railslocated on both sides of the bucket, supporting and guiding it in thedirection of conveyance; and a swing rail positioned pivotally in theunloading position on the horizontal conveyance route, said rail forminga sinusoidal curve so as to enable the body to rotate while supportingthe body, being able to move away from the body.
 12. The conveyor ofclaim 11 , wherein the bucket is equipped with a roller at the bottom ofthe body, said roller being able to contact with the swing rail.
 13. Theconveyor of claim 11 , wherein the bucket is equipped with a wheel shaftjutting out both sides of the introduction, supported by the guide railsvia the wheel shaft.
 14. The conveyor of claim 11 , further comprisinganother bucket following the bucket, wherein the introduction is linkedwith the introduction of the following bucket via a bar.
 15. Theconveyor of claim 13 , further comprising another bucket following thebucket, wherein the body has at the upper portion a flange extendingbackward to rest on the wheel shaft of the following bucket with the aidof the flange.
 16. A bucket conveyor for conveying loose grain, in whichthe bucket angle must inevitably change according to the direction ofconveyance, said conveyor comprising: a bucket having an opening leadingto the interior of the bucket at the front, and a dead spaceconstituting part of the interior at the rear, the space not filled withloose grain when grain is loaded from above to or beyond the level ofthe opening, its volume being larger than the filled volume immediatelybelow the opening; a hopper being able to adjust the feeding port angleby rotating on a support shaft stationed outside the bucket conveyancetrack; and guide rails supporting and guiding the bucket in thedirection of conveyance, forming a circular arc with a sharp curve underthe hopper.